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Everything posted by Strange
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1927 B and C are the same thing. And that is what happened. And is still happening. The cosmological constant represents something called "dark energy". We don't know what this is so many different ideas (hypotheses) are being tried out. These are different possible explanations some of which may lead to different theories (either variations of the big bang model or even drastic changes to it). People are still checking the original observations and seeing of the data still holds up when we look at more and more galaxies in case the observations are in error (so far, this has just confirmed the acceleration. Huh? That makes no sense. That is what I said: the constant was added so that the results of the equation (i.e. the predictions of the big bang theory) match the observations. There is nothing being "protected". We just need to make the equation fit the observations. Yes, I think you forgot to try and understand what you read. You filter everything through your prejudices and preconceptions, instead of actually reading it. You are so convinced that modern science has got everything wrong that you distort and twist everything you read to convince yourself that there is something rotten in science. It is very tiresome.
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But red shift is just one "symptom" of time dilation. So, for example, the light from a supernova falls off at a very characteristic rate (the "light curve"). For more distant galaxies, the light curve is slowed by exactly the same amount that the light is red shifted. "How" is a tricky one. In the case of special relativity, where we are just concerned about relative velocity, then we can view this as a rotation of the coordinate system. The faster an object is moving through space, the less it moves through time - it swaps some of its time dimension for some of the spatial dimension. Similarly, for gravitational time dilation, although it is not a simple rotation, you can consider that the time dimension is shrunk while the spatial dimensions are stretched (although the details of what happens are complex). So much so that, at the event horizon of a black hole, the space and time dimensions get completely switched: the singularity ceases to be ahead of you, and is now in your future (and what used to be your future is now a position some distance ahead of you). And they say you wouldn't even notice! I would refer you back to that graph earlier which showed the relative effects of velocity and gravity.
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Says the guy who is acting all hurt when people try to explain how science works ...
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All particles are quantised excitations in the relevant field(s). I read a really good article about this recently but I can't find it again (it was explaining the Higgs mechanism, I think.) This one might do instead (but probably requires more work): https://profmattstrassler.com/articles-and-posts/particle-physics-basics/fields-and-their-particles-with-math/
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The time dilation will change as they approach the area of increasing gravitational potential. There are multiple causes of time dilation. One is cosmological, due to the changing scale factor of the universe. So distant sources are time dilated, which is why we see red shift (they are the same thing).
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Another important point is that the speed of light limit only applies "locally" to things passing each other. The expansion of the universe is a scaling effect (not a "speed"). This means that the speed at which any two points are separating is proportional to how far apart they are (by simple geometry). This means there are (and probably always have been) points that are far enough apart that the speed of separation is greater than c. We can even see galaxies that are receding at more than the speed of light.
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No. Satellites in orbit are in free fall and their clocks run at different rates depending on altitude. Definitely not. That is why distant galaxies are red-shifted (and therefore time dilated).
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Of course it was. http://www.npl.co.uk/science-technology/time-frequency/time/faqs/was-2000-a-leap-year-why-who-decided-this-(faq-time) As you don't say which information, I can't check this. However, as you clearly don't have a clue, I will assume it is correct.
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What? This sounds more like some incoherent conspiracy theory than computer science. Of course 2000 was a leap year. Everyone has always known that it would be. No one magically retrofitted the extra day. It was always there. And it has nothing to do with the Y2K problems (which were all fixed on time, apart from a few tiny hiccups). Sheesh.
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Still not making much sense. There is no obvious relationship between the rate of fall in a vacuum and in a medium where the terminal velocity becomes significant.
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I'm not sure. I would guess yes, but it may be possible to come up with some pattern of space-time curvature that does not cause gravity. Actually, it is more accurate to say that space-time curvature is gravity, rather than causes gravity. (The latter implies that gravity is something separate from the space-time curvature.) And note that is it space-time curvature, not just space. Yes. And a few other things also contribute: momentum flow, stress, etc. You can find the gory details here: I think that "most curved" may correspond to the presence of mass-energy (and therefore where things will move towards). But that probably needs a Mordred to answer. All particles are also waves (or have wave-like properties). But this is not relevant for gravity. That just depends on their mass-energy. Gravity is just one of the effects of the curvature of space-time (others are things like time dilation, red-shift, etc). They are both measurable quantities (because they are the same thing). But not substance. It is measurable (pull out a ruler, for example) but not a substance.
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The Gullstrand-Painlevé coordinates only apply to an unchanging, spherical, non-rotating mass in an otherwise empty universe. That might be a reasonable approximation to a few other cases. But it isn't clear that gravity can always be re-interpreted as the "flow of space". This seems to be a bit of a special case. However, the description of gravity as the curvature of space and time is universal.
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Yes. No.
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What is the total mass + energy of the charge carriers? That is the source of gravity. Please be specific (i.e. use numbers). Plasma physics is immensely complicated and it isn't good enough to make wild guesses about what might happen. Physicists use supercomputers to run simulations to understand the possibilities. A scribbled drawing just isn't as convincing. How can it become infinitely bigger? Not really, no. Atoms and black holes have almost nothing in common.
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If the probability for any toss is 1/N then the probability for the first toss is (by definition) 1/N. Because the first toss is just one of "any".
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One problem with this is that magnetic fields will have no effect on dark matter. Also, because it does not interact via electromagnetic forces, dark matter will not respond to gravity in quite the same way as normal matter (which is why it is distributed throughout galaxies, rather collapsing into "clumps" like stars and planets). If anything, I would guess that the absence of a magnetic field would reduce the gravity because it means the total energy is lower. But this would be too small to detect anyway. A black hole is not infinite. (I have no idea what "infinite relative space" means.) Basically, you are just making stuff up that has no basis in science or reality.
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Maybe you providing an explanation and not just incomprehensible diagrams would help.
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Ah yes. Well spotted. (Are you proof-reading and fact-checking all my posts today ...) And that is a much better way of calculating it.
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And I have run out of time to edit it! Aaargh!
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Hard to say, as you don't show how you calculate anything! But the numbers look way to big to me. Let's see: Surface area of moon = 38 million m2 Total energy falling on moon per second = 1/2 x 38x106 m2 x 1426 J/s (watts) = 27x109 joules/s Total mass falling on moon per second (from e=mc2) = 27x109 / c2 = 3x10-7 kg/s Not sure how to equate that to the total mass between the Earth and Moon, but maybe multiplying by light travel time (1.3s) would be about right. So we are talking about a total mass of about half a milligram. As you say, not really significant. More significant could be the mass of the Moon directly above.
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Who knows, without a mathematical model to test. (But it certainly doesn't look like any black hole representation I have seen.)
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You may think you can predict the motion of the universe but there is only one way to know if you are right or not. And that is to produce quantitative predictions that can be tested against reality. That means using mathematics. So, I would say that it is a credibility requirement imposed by the universe.
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The simplest model is the Schwarzschild metric. http://www.daviddarling.info/encyclopedia/S/Schwarzschild_black_hole.html This describes a non-rotating, uncharged black hole (in an otherwise empty universe). It is thought to be a good approximation for many cases. Slightly more realistic is the Kerr metric, which describes a black hole with angular momentum (e.g. formed by a rotating star). http://www.daviddarling.info/encyclopedia/K/Kerr_black_hole.html
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What do you mean "proved his equation"? Do you mean did he compare the predictions of the theory against observation? If so, then the answer is yes. And when those observations showed that the universe was actually expanding, the cosmological constant was set to zero. Now we have seen that the expansion is accelerating, the value has been adjusted again. THIS IS HOW SCIENCE WORKS. This is a moronic statement and this is NOT how science works. Of course. That is why it is stupid to talk about "proving" things in science. No.No. No. No. NO. The constant was added so that the equation matches what we observe. That's it. No. No. No. No. NO. It is not a proof of anything. It is just a matter of adjusting the model to match reality (as accurately as we can). We can't "prove" it. You cannot prove anything in science. However, the model will be continually tested by making more observations. The data from these may be used to adjust the value of the cosmological constant and other parameters. Of course. That is always true of all science. Science is always subject to change when new data or evidence is obtained. That is how science progresses. Only an idiot would say that we should never change our models. The equation was updated based on evidence. Therefore it matches the current evidence. Further observations will be used to check (and either confirm or change) the value of the cosmological constant and other parameters. Because that is how steichen works. What does it matter what we call it? Most equations are not named after the people who actually invented them, anyway. Many (most? all?) theories are changed after the original version. And why does changing the value of one parameter mean the name has to be changed?
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Important to note that the ejected matter never actually entered the black hole. Once matter (or light, or anything) falls into a black hole, it can never emerge.